The coexistence of heterogeneous sub-networks in 6G poses new security and trust concerns and thus calls for a perimeterless-security model. Blockchain radio access network (B-RAN) provides a trust-building approach via repeated interactions rather than relying on pre-established trust or central authentication. Such a trust-building process naturally supports dynamic trusted services across various service providers (SP) without the need for perimeter-based authentications; however, it remains vulnerable to environmental and system unreliability such as wireless channel uncertainty. In this study, we investigate channel unreliability in the trust-building framework based on repeated interactions for secure wireless services. We derive specific requirements for achieving cooperation between SP and client via a repeated game model and illustrate the implications of channel unreliability on sustaining trusted access services. We consider the framework optimization to guarantee SP-client cooperation, given a worst-case channel condition. Furthermore, we introduce the concept of cooperation region to represent the robustness of the trust-building process and explore the maximum cooperation area to enhance service resilience. Finally, we present simulations to demonstrate the system performance over fading channels and verify our results.

翻译：6G中异构子网络的共存带来了新的安全与信任问题，因此需要一种无边界安全模型。区块链无线接入网络（B-RAN）通过重复交互提供了一种信任建立方法，而非依赖预先建立的信任或中心化认证。这种信任建立过程天然支持跨不同服务提供商（SP）的动态可信服务，无需基于边界的认证；然而，它仍然易受环境和系统不可靠性的影响，例如无线信道不确定性。在本研究中，我们基于重复交互的信任建立框架，研究了安全无线服务中的信道不可靠性问题。我们通过重复博弈模型推导出SP与客户端实现合作的具体要求，并阐明了信道不可靠性对维持可信接入服务的影响。考虑到最坏信道条件，我们对框架进行优化以保证SP-客户端合作。此外，我们引入合作区域的概念来表示信任建立过程的鲁棒性，并探索最大合作区域以增强服务弹性。最后，我们通过仿真展示了系统在衰落信道上的性能，并验证了我们的结果。